Stoppers are widely used to seal a vessel or to limit the ability of the contents to escape from the vessel. Some stoppers are solid and thereby prevent any of the matter from entering or leaving the container, while others may include one or more apertures that allow one or more tubes to be inserted into the container. When more than one tube is inserted through a stopper into a vessel, the tubes may be used for different functions or may carry different materials. For example, one tube may be used to insert a certain substance into the vessel, while another tube may be used to remove matter from the vessel or to insert another substance into the vessel. The tubes also may be inserted into the container at different depths so as to remove different layers of matter, or to remove different phases of matter, such as a gas or a liquid. Thus, it is important that one is able to distinguish between the tubes and the different functions of those tubes.
Clear or translucent tubing is widely used and can be helpful in some situations in distinguishing between the different tubes. However, in many situations, being able to see the contents of the tubing does not enable one to distinguish between the tubes. Different tubes may be carrying substances that look similar or they may be carrying clear or substantially transparent substances. Moreover, it may be necessary to distinguish between the tubes at a time when they are empty, such as during the assembly and set up of a particular arrangement of tubes and vessels, in which case being able to see through the tubes is unhelpful.
Various method and techniques have been used to improve one's ability to distinguish between different tubes. One such method is to attach a label or some other indication to the tube and/or the stopper using various adhesives. However, such adhesives generally have not been found to reliably bond to the materials commonly used to make stoppers and tubes. Moreover, physically attached signs or labels can, overtime, become worn and illegible, or may eventually become detached from the appropriate stopper or tube. Such labels may also be difficult to read from a plurality of different angles and may, depending on the environment in which the stopper and the tubes are used, become difficult to read due to debris that may build up on the labels.
Another method or technique used to place identifiers on stoppers and/or tubes consists of placing labels on the outside of the tubes or stoppers and then molding over the labels. This overmolding technique creates a raised section on the stopper or tubing and involves a additional manufacturing process, which generally results in additional manufacturing costs.
Accordingly, it would be advantageous to provide a structure or apparatus that would enable someone to distinguish between different tubes and/or stoppers regardless of the environment in which they are used. Moreover, it would be advantageous to provide such a structure or apparatus that could not easily be removed or worn off and that would not also require additional manufacturing processes. Additionally, it would be advantageous to provide a structure or apparatus for differentiating between different tubes and/or stoppers that would be effective when viewed from any of a wide range of directions. Furthermore, it would be advantageous to provide such a structure or apparatus that would not physically distort the shape of the tubing or other parts of the tubing assembly or contaminate the substances used in connection with the tubing assembly.
Accordingly, it would be advantageous to provide an apparatus for distinguishing between tubing assemblies that has any one or more of these or other advantageous features.